« ПретходнаНастави »
tains an equal, and in some instances a greater, amount of gold from one of these exhausted placers. We may, therefore, regard the surface deposits of these sections as prolific sources of wealth for years to come. This conclusion is based on the facts which past experiment has demonstrated, and which are acknowledged throughout the State by those who have given any attention to the subject.
In selecting the counties of Placer and El Dorado, as illustrative of the character of the eastern range of deposits, I would not be understood as expressing any preferences of productive capacity, or of a better defined range of these deposits; they were selected from the fact that they held a more central position in relation to the above, than for any other purpose; and they do not, to my knowledge, afford any better illustration of the characteristics of this district than the counties of Sierra, on the north, or that of Amador or Calaveras, on the south; in fact, this range is much better exemplified in the county of Sierra than at any point south of the latter.
MIDDLE PLACERS.-By this term is expressed that range of country which is situated at the average distance of about twenty miles from the line of the higher foothills, or having its western border within about four miles of the edge of the plains, comprising a district of country twelve miles in width and three hundred in length, having a trend parallel with that of the mountain chain in which it is situated; it covers an area equal to about six thousand
On this range is situated what is denominated the surface workings, although there are some instances in which the deposits of drift containing gold lie nearly as deep as those alluded to in the preceding article. This, however, is not the general fact relative to these districts, and the labor and expense of extracting the metal, consequently, is not as heavy. The ordinary depth of the placer drift in this district, ranges between twelve and forty feet; it is composed of a more heterogenous collection of stones than the deposits of the higher range; in the latter, the pebbles and boulders have but few varieties, while those of the middle placers are composed of many; 80 much so is this the case, that it is often difficult to distinguish what rocks predominate.
The 'bed rock' of these districts is composed mostly of slates elevated to high angles of inclination, or the same rocks changed by heat, in some cases to that extent as nearly to obliterate their former structure; their transition has been so complete that they have assumed the character of true porphyries; this must have occurred prior to the deposition of the drift, as these deposits bear no marks of igneous action since they were deposited. In some localities the drift beds are found resting upon the granite direct, the latter rock often presenting evident marks of the action of water.
In examining the gravel from this district, we will often find the stones which are peculiar to the eastern range mingled with those of more recent date, and which are often found in closer proximity in situ; with the above is also found more or less of the smaller gold of the upper districts commingled with that which is incident to the middle sections of the State.
These facts naturally lead us to the conclusion, that at the period in which the gravel drift of the middle placers were deposited, the country to the east was subjected to the action of floods which must have been somewhat violent in their character. I am not prepared to say, at this time, that the deposits of this district of the State were formed during the period of the Northern Drift
, for there are some features wanting to establish that point conclusively. Should the above fact be ultimately established, there are attendant circumstances that will prove the eastern range to have preceded that period, and which has been alluded to in former reports.
The economical value and extent of the middle placers, is the principal object of their notice in this place; and we will, therefore, direct our attention to that particular point. It is upon this range of country that the greater proportion of the mining community are located, and more particularly upon the central and eastern portions of the same. The cause of this is obvious, for from the nature of the ground to be operated upon, segregated labor is more prosperous, and small companies, with limited means, can prosecute mining with better success and profit than in the heavier workings of the eastern range of placers. The labor and incidental expenses for facilities in the extraction of gold, are much less and more easily obtained, as a general rule, than in the former case; hence, men who are possessed of limited means usually occupy the middle sections before entering the field of the more lengthy operations that are conducted in other districts.
The introduction of water by artificial canals into regions lying remoto from natural streams has had the effect to develop further the fact, that but limited sections exist in this district in which the staple product of the State does not abound. From the above facts we should be led to infer, that a much larger population than that at present found in these districts should follow under the circumstances: it should be thus, but there are causes which at present operate to prevent such a result, the principal of which, is the want of a sufficient supply of water to conduct mining operations to that extent which the character of the country requires. The natural supply of this material seldom exceeds four months of the year, in amounts that would be equivalent to subserve the above purposes, in the greater proportion of the mining localities of this range, and this too at that season when labor is nearly suspended from inclemency of the weather. In order, therefore, that an extensive population should be found upon the unoccupied portions of this part of the mineral district, the introduction of water by artificial means becomes an essential requisite.
An increase of our mining population in any district of the State, has no tendency whatever to excite any fear of the exhaustion of the mines of that locality to which they may chance to wend their way; for it is now admitted that sufficient room for labor abounds in any of the mining settlements, for a much greater number than those who now occupy them. The introduction of water by canals through an unoccupied portion of the State, is as certain to bring in an active population along its line, as the fact that such an agent is known to exist; as it is well known that nearly the entire surface contains a sufficiency to largely pay for labor in its extraction.
So far as the middle placers have been opened, they have thus far proved productive to an eminent degree, and new placers which had been developed within this range have, so far as known, proved fully equivalent to those which have preceded them; and there is no good reason that can be advanced for the untenable position that has been assumed, that the present theater of operations is the finale, any more than for a similar opinion which was entertained four years since in relation to those localities at that time occupied, and which are still yielding their annual quota nearly the same as before.
VALLEY MINES. — The valley mines are those districts which are situated among the lower foothills of the mountains, and extend westward from thence into the eastern edge of the plains of the San Joaquin and Sacramento to the extent of three or five miles. These mines are distinctly traceable from Chico Creek, in the county of Butte, on the north, nearly to Snelling's Ranch, on the Merced River, to the south-having a linear distance of about two. hundred and fifty miles. The position which they maintain, or whether they exist at any point north of the first named boundary, and south of Fort Reading on Cow Creek, in the county of Shasta, I am at present unable to state, not having passed over that particular district during the past season. But the opinion may be safely entertained, that they are continued through the latter district, and that the placers of the Upper Sacramento Valley,
alluded to in the preceding pages of this report, are but the northern termini of this belt. The valley mines are situated on what has been spoken of as constituting the higher terraces of the plains, and are composed of alluvial drift mostly, which have been derived from the lower hills adjacent to their borders. The gravel of the lower beds is usually small, and composed of the pebbles found in the conglomerates commingled with the smaller stones, which have been conveyed by the agency of water from the approximate portions of the middle districts. The gravel is usually much discolored by the ferruginous materials with which they are intimately commingled, and all the beds containing gold, from the surface to their greatest depths, partake in a high degree of the same peculiar characteristic. The deposits are found to extend to depths varying from three to eight feet, and rest on sandstone, slates or clay beds above the latter, and are the most shallow of any of the placer ranges as yet discovered in the State, and at the same time the most easily worked.
It has been generally supposed, that the entire valley-lands skirting the foothills, possessed but limited amounts of the precious metals; and that when such lands containing gold were thus known, the deposits have been regarded as purely accidental. Such is not the case, however, and if it were, the same rule would be equally applicable to every other portion of the mining districts of the State. Since the days when that opinion prevailed, there have been circumstances occurring, at different times, respecting the true characteristics of these lands, which have had a tendency to modify the views then entertained respecting them, to that extent that those views have now become entirely obsolete, and the valley mines are now considered nearly coextensive with the middle or upper districts, and they probably fall but little short of the latter.
Should an ample supply of water * be furnished to open this entire range of placers, we have not a population sufficient to occupy and improve it, aside from those engaged in similar occupations in other parts of the State. A large proportion of these mines will, therefore, remain untouched for many years to come, and improved only in isolated portions, where the conveniences of water are easily obtained.
Most of those who are at present engaged in this district, are men who have formerly occupied themselves in the older and mountain districts since 1850, and are, therefore, capable of judging of the comparative value of a placer of this kind, with those of other sections. Their experimental knowledge is, therefore, of some value as a criterion, to judge of the prospects of these mines, as being remunerative for labor, if no other more conclusive considerations presented themselves.
Within the past year, where the advantages of water in sufficient quantity existed to conduct operations in mining, these districts have yielded as fair average returns for labor as any district of the State. And though situated so far to the west and into the plains, where we should have expected to find little else than fine 'drift gold,' it is proved that in the majority of those localities which have been opened, that metal equally coarse with much found in the more elevated districts, has been taken from the valley mines. This fact is sufficient to do away with the idea that the deposits of the plains are merely accidental, as they have been termed; they have evidently been derived, in a great measure, from the breaking down of the adjacent sedimentary rocks, which contain veins of auriferous quartz, the disintegration of which has furnished the material which we now find distributed throughout the range; and from that cause we may expect that these placers will prove
* A large amount of capital is invested throughout the State in the erection of water-courses for the supply of water for the purposes of mining. The table of Canals and Water Companies, on page 275, will exhibit the number already constructed.-[ED.
equally advantageous for operation on an extended scale, as many of the more ancient beds of the Sierra Nevada.
The limits of that district containing gold upon the plains, I should estimate as carrying a line parallel with the foot-hills, and at a distance of four miles west of the latter, and which should be considered mineral lands in the strictest sense in which that term is applied, and they should be subjected to the same jurisdiction that now obtains in the mountain sections. Such lands under our present system of laws, are not subject to entry, and the fact is thus mentioned that their position may be better understood.
From the best information obtainable from all parts of the State, it is believed that the amount of ground in actual occupancy, and under improvement for mining purposes, does not probably exceed four hundred square miles, one-fourth of which area may be included in what are known as old placers, and which are still productive.
From what has been said of the areas comprised within the lines of the different ranges, as given in the preceding pages, it will be seen that we have still enough and to spare for all who are present, and for all that may hereafter arrive, for at least the next half century. There need be but little fear of their failing to yield their annual crop of gold, as long, perhaps, as our valleys will yield their crops of grain.
The aggregate areas amount to about eleven thousand square miles, that is known to contain gold; and when this is compared with the area actually occupied, the latter will be found to comprise but a mere mite of our available sources. With our present population of the mining districts, and the broad expanse of territory over which they are spread, they appear like mere specks dotting the surface of an inland sea, so indistinct as scarcely to be appreciable on the broad expanse by which they are surrounded.
MINING, AND THE VARIETIES THEREOF. PLACER MINING.—Placer mining to California, is what coal mining is to Pennsylvania, and the great coal districts east of the Rocky Mountains; and we are fast approximating to that day when its subterranean operations will equal, and in many cases exceed, the latter. Should 'there be those who foster doubt on this point, and doubtless there are many such abroad, I would respectfully suggest to such, a visit to the upper portions of the counties of Placer and El Dorado, with those of Amador and Calaveras on the south, and those of Nevada and Sierra on the north. In these counties they will find an ample field of operations, on which they will find but little difficulty in forming an opinion of the character and extent of the workings beneath the surface and the means employed to consummate the end. They will find the engineer with his levels as carefully adjusted and applied, as though his survey was instituted for the leveling of a rail track, and the necessities of accuracy in the selection of the most feasible point to tap the heart of the mountain, is equally as great in the one case as in the other.
The placer miner of the present day in this section of the State, estimates the costs of the operation in which he is about to enter with all that care and attention that would be bestowed upon any other enterprise where the sum of ten to thirty thousand dollars is the sum to be invested, and where his interests are involved to that extent. It is not uncommon to find amounts equal to the above, invested in our larger operations now in progress of working, and a few instances among many, may serve to illustrate the fact. I will mention but two or three in connection with this part of our subject.
The cost of opening the Mameluke Hill, near Georgetown, by the parties interested, exceeded forty thousand dollars, while the receipts from the same during the period of little more than one year, have exceeded five hundred thousand. Another case is that of Jones' Hill
, the opening of which has already risen above thirty-four thousand dollars, the receipts being above two hundred and eighty-four thousand dollars ; and still another in the county of Nevada, (Laird's Hill*) the expense of opening was nearly forty thousand dollars, while the receipts from the latter in June last, had reached the sum of one hundred and fifty thousand—the resources of either are as yet in anything but an exhausted condition. The above are mentioned only for the purpose of conveying a better idea of the expenses and profits of what is denominated deep mining in this State; and the localities named, form but a small proportion to the aggregate of similar workings.
In the counties of Nevada, Sierra, Placer, El Dorado, Amador and Calaveras, there are scores of adits and other workings of smaller dimensions, which have already cost sums varying in amount from ten thousand dollars upward to the figures given above, and from which proportional profits have been derived. The mining districts abound with evidences of wealth like those above, and they possess equally as strong evidences of permanency of character, and it would be no difficult matter for the incredulous to banish their incredulity, if they will but take the trouble to investigate the facts which nature and individual enterprise have placed before them.
An idea of the necessary expenses that must be incurred in conducting these branches of placer mining, can be obtained only by an examination of the adits which have been driven, in prosecuting these labors. There are but few which are less than three hundred feet in length, and many that range from ten to twelve hundred feet, and of a size sufficient to use a horse within, for the purpose of delivering the earth to be washed at the sluice or the attle to the end of the tram-road. These adits are driven, in some cases, hundreds of feet through solid rocks, and when thus conducted, they often penetrate the very center of a mountain; or, as in the case of the high ridge south of Placerville, they have not only reached the center, but have passed entirely through the ridge."
An estimate of the enterprise and perseverance of the mining population of this State may be formed from the character and extent of this branch of mining The tunnel of the Table Mountain Consolidation Company, of Butte County, extends a distance of several hundred feet through a solid rock, six feet in hight by four and a half in width. Table Mountain, Tuolumne County, has also been tunneled in many places to a distance of over fifteen hundred feet. One company alone has made an aggregate of four thousand three hundred feet of tunneling, averaging from four to six feet; fifteen hundred of which were so intensely hard as to require blasting before it could be penetrated. The estimated value of the labor performed on this work alone, is over one hundred thousand dollars.
“HYDRAULIC MINING.-In other parts of the State, the heavier placer operations are conducted in a different manner. In place of the adit, a broad ditch is carried through the hill, and the entire hills removed to their base by hydraulic washings. This system of working, as conducted in this State at present, will compare very favorably in magnitude with any system of mining operations of the Atlantic States, or even in many parts of the older continent, and from the success which has attended it, bids fair to advance much beyond the limits to which it is now confined.”
RIVER MINING.—This branch of mining is extensively carried on for about six months in the year. During the summer months when the waters of the rivers are low, the streams are diverted from their natural channels by means
* It is said that the gentleman from whom this hill derives its name, has taken out from the placers of this state, since 1850, over $500,000.—[ED.